"bo0ger1" .@. wrote in
:

*Emphasis mine. Here, you attribute water changes to a herd
mentality;

Do you know why I refer to it as the 'herd mentality' or 'herd
behavior'? Because most people in this forum (and most people that I
have discussed the topic with) perform water changes ONLY because
everyone else is doing it.

Really? What has convinced you of that? Thus far, the only thing I've
seen to that end is that you've cited errors at Wayne's site wrt valence
state and number of oxygens on nitrite, nitrate, and ammonia. Despite
those errors, did you also find the underlying theory of the nitrogen cycle
to be somehow un-sound?

They don't understand why they are doing it
AND for this reason they don't know that they don't have to do it.

Read more on the 'herd behavior' he
http://en.wikipedia.org/wiki/Herd_mentality


Yeah, I don't see how this applies when

I say again, what evidence could I possible offer ??

The same things I've been repeatedly asking for, please.


Tank size? 75 G (I'm not sure how this qualifies as evidence)

Not evidence, but context. Qualification for, and quantification of, the
information you offer.

Tank age? 2 years (I'm not sure how this qualifies as evidence)
sump? Yes (I'm not sure how this qualifies as evidence)
sump size? approx. 5G (I'm not sure how this qualifies as
evidence)
nutrient export? ???

Meaning, do you use your sump as a refugium, to grow algae(s) as a
supplemental means of nutrient export? If yes, what are you growing?

http://www.reefland.com/rho/0105/main2.php

1/2 way through that article, you'll find a pic and discussion about the
Chaetomorpha that blackhole is using to export nutrients.

fish species/size? (I'm not sure how this qualifies as evidence)

It quantifies the fish mass (and the corresponding amount of waste) which
can be handled without the need for water changes as a means of nutrient
export.

inverts species/size? (I'm not sure how this qualifies as evidence)

It identifies whether or not the species you are keeping are relatively
robust, or prone to problems related to less-than-perfect water quality
(as, ofr example, some SPS corals are famous for).

recent water test results?
Do you track water parameters regularly? I use to, but always same
result. 0ppm Nitrate, nitrite, ammonia. pH normal range. Observe any
fluctuations? No

You stopped after only 2 years? I'd slow down if things looked to be under
control with a tank, but I'd test aboutmonthly, since water parameters
usually change in advance of health issues with the occupants. Since
you've stopped, please consider a quick look at your current water
parameters, just to verify that, today, you have the same results you did
when you last tested.

Equipment setup (skimmer, lights,powerheads, sterilizer, carbon, phos-
reactor, other filtration etc)? (I'm not sure how this qualifies as
evidence)

I'm trying to establish/understand the conditions under which you've
obtained success with NWC. If there are other filtration factors/methods
at work in your system maintaining water quality, I'd like to know about
them, please.
Lights and powerheads go towards general suitability of comparing your
results to those of a reef system with inverts. If, for example, you only
maintain flourescent lights for observing your fish, then you might expect
that low light is also helping to control your rate of algae growth. With
some SPS reef systems running 4-6 Watts/gallon of broad spectrum Metal
Halide lighting, smaller changes in water quality become larger problems
with algae growth, as the algae has all the light it needs to grow
prolifically.

Feeding schedule? (I'm not sure how this qualifies as evidence)

As with fish mass, it helps to understand how much of a nutrient load your
system is handling, without the need for water changes.


A pic would be nice, as many of us can gauge general tank health from
the appearance of the inhabitants, especially inverts, who tend to
reflect clearly the quality of the water in which they're raised.

My inhabitants appear healthy. I am certain that they would not
appear unhealthy to you.

NP. Forget the picture. I'll take your word that all of your occupants
are healthy and happy.

Oh, Man! Did I forget two BIG ones!

How much live rock (pounds), and/or live sand in your system(depth in
inches)? What kind of live rock (point of origin)?

What does your detrivore cleanup squad look like (hermits, snails,
sandsifters, etc)?

It's not rocket science dude.

What happened to that special insight into tank chemistry/biology
that I needed?

That's what makes this thread so sad. If you understood why water
changes were not needed (at the biological level) you would understand
how really simple (not rocket science) this topic is.

Please expand on this idea. I want to understand, at the biological level,
why water changes are not needed. Take me through it, step by step,
please. To give your discussion context, my understanding of chemistry is
good enough that I've built a successful career on it, but my understanding
of marine physiology/biology is vanishingly small.

Instead of doing water
changes...ummm....don't do water changes.


The above conflicts, more or less directly, with this;

"I think the real reason they do it is for a lack of understanding at
the chemical/biological level. It is easier for them to do a water
change than
to grasp what is going on in their tank at a biological level."

Which is it?

I fail to see the conflict.

The former implied to me that anyone anywhere (with a FOWLR or reef setup)
can quit their water changes, starting today, without deleterious results
on their system. The latter implies that the way in which you transition
from WC to NWC requires some education into chemistry/biology before doing
so, and thus NWC may _not_ be as simple as the first quote implies.

I think you are right about water changes, to a certain extent, but
i'm a bit more cautious about which setups I would consider NWC for,
especially reef type setups.

My experience has directed me to the following conclusion (again, take
it or leave it): Water changes weaken your bioload. Bacteria exist
in your aquarium that take care of ammonia, nitrite AND nitrate. The
end result is N2(g) and H2O. I would suggest stopping your water
changes gradually (gauge by testing) to allow your bacteria to
proliferate.


My experience tells me that there is an upper limit to the load you can
place upon the bacterial colony in a tank. I accept that NWC change
systems are reasonable and certainly possible, but I suspect that you need
to start (and possibly maintain) them on the low end of the total load to a
tank's bacterial colony. At this point in time, I'm trying to get a feel
for where your tank fits into the range of possible bio-loads.

BTW, I've usually seen the term "bio-load" as an expression of the amount
of vertebrates/invertebrates vs. tank/system size. A larger bio-load means
there are more fish in less space. You seem to use the term differently.
Could you post a quick comment on how you use the term?

Thanks!

DaveZ
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